Gttn synchronizer



eamed Mar. 8, 1932 p c Application filed April 2', ;}This invention relatesto a machine gun 5; synchronizer unit, and more partic'ularly to a'caln impulse'generator. v' a ';The obJect' Of th's invention is to provide a: ;more compact arralngement of a synchron-izer and a'n improved means'ofmaintaining proper al'ghm'ent between the cam andlits 1 follower. {.i v f 1 yWiththe foregoing and other objectsjin i miview;the in ention resides in the'combina- -v panying specification and appended'claims,

illustrated in the accompanying drawings, in

I WFigure' 1 is ia iew in alongitudinal secti on through the device, and Figure 2' i's' a view partly in longitudinal fgfysection through the device taken on a plane 'atrightan'gles to that shown in Figurefl. Y Figure 3 is a; detailed view showing'the fol-l I lowerand a'particular type of lobe and thefollowe'r. Figure 4; is a similar'deta'iled view of a '1 modification ofthe'followerand a'tangential camwith-two lobes; r r Y Itis a common practice to provide means wherebya machine gun mounted on an aero plane may be'so synchronized with an inter nal combustion-engine, and with the rotation of the propeller driven thereby, that the gun without-interference. e j Referring more particularly to the draw- .unit eomprisinga casing 1- in which there is mounted a shaft J 2" which may be driven V A ball bearing assembly is I provided for the rotation of the shaft and consists" in theouter races 4: journaled in a sleev'e5 secured to the casing by set screwsi6, and inner races 7 secured with thelshaft', the races being 'held" against the longitudinal movement by an intervening sleeve'8' and an end nut Q'engaging the shaft, and by the inwardly dependingflange 5 of the sleeve 5. Suitably 'keyedto and arranged interiorly j plane" engine.-

" "st'ructionfhereinafter setforth in the accoma .v certain embodiments of the invention being cain' with one j 'camfollower ina'direction indicatedin Figure 2 as a downwardly one. Accor'dingly' may be discharged I at frequent intervals 7 through the-path of rotation of the propeller ,ingsfthere s provided such a synchroniz er.

throughits integral bevel gear 3'by the' aeroif WINTHRoPLs. shame or FARMINGDALE; NEW YORK, ASSIGNOR To FAInoHILn Avie ,TIONICORBQBQATION, on NEW YORK, N. Y., A CORPORATION or DELAWARE Y Ger: sizncnnoniznn 1930. Serial No. 440,893. 7

of'the shaft 2-at 22 is a'shaftlOwith an enlarged portion recessed to receive a ball bearing assembly 11 and screw threaded to receive a retaining nut 12. g The shaft 10 terminates in an integral *cam v13 which maybe of the type-shown in Figure 3or asingle or double l obed tangential cam shown infFigure 4. The camshaft runs at twice the engine speed to fire with a two-blade propeller, or which I p I N v may be a double-lobe cam-,- as shown in Figtion offparts and in thedetails of the-con--,

mover ofthe gun actuation means, is ournaled within'an extension of'the casing'for' reciprocal movement in a' direction at right angles to the axis of rotation of the shaft andagainst the action of the spring 21; The follower is recessed'to form"straightfhori zontal'end faces15 and 16, and-longitudinal face 17 and the recess isof a greater length than the'largest diameter of the lobed cam.

The function of the cam is to operate the the face 16"is'rounded, as shown'in dotted lines in Figures 3 and 4, to receive impacts from the lobe, or'lobes, of the "cam when the shaft 10 is rotated. The camfollowe'r is re turned by means of the spring 21' which is of such capacityas to hold the cam fol-lower in contact with the cam at all'operating speeds. Theupper end of the cam follower ispro- -videjd with a slot 20 which maybe so an ranged astobecaughtby a suitable sliding pin'operated by a trigger., As will be readily understood without actual: disclosure, when the pilot: desires tefire his machinegun, he

pulls a trigger which will pull a pin out of engagement with. the notch 20 in'the cam follower. This permitsfthe spring 21 to force theface 16 of the follower against'the cam, and the follower thus receives regularly timed impulses fromthe 0am until such time as the slot2'0 is engaged by a pinto-holdthe cam follower out of engagement with the cam. The distance between the faces 15 and 16 is such that allowsrsufiicientclearance under itheseconditionsfor-the camtolrotate without March, 1930. so

made possible by said key connection, a cam follower adapted for use as an impulse gen- {ierator for the firing mechanism of said machine gun, said follower having formed therein a longitudinal recess with end faces, said follower being notched to receive a restralnmgmember and said recess being of suflicient length to allow the rotation of the cam there'- in under these conditions without striking :IO-either of said end faces, said follower being I Q provided with a spring for forcing the lower end face into constant engagement with said j rotating cam upon the release of said notch by I the restraining-member. v g 9. In a device adapted for use as a machine 1 gun synchronizer, a hollow rotary driving shaftadapted'to be actuated by a suitable prime mover, a driven shaft keyed to said driving shaft and adapted to be rotated thereby, atangential cam arranged on one end of 7 said driven shaft, and means for maintaining said driven shaft in adjusted positions made 7 .possible by said key connection, a cam follower adapted for use as an impulse generator for the firing. mechanism of said machine Ijgun, said follower having formedtherein a longitudinal recess with end faces, said follower being notched to receive a restraining member and saidrecess being of sufficient length to allow the rotation of the cam therein under these conditions without striking either of said end faces, said follower being provided with a spring for forcing the lower end face into constant engagement with said rotating cam upon the release of said notch by the restraining member, a plurality of set screws being provided for the purpose of maintaining said cam in alignment with'said follower.

' 10. In a device adapted for use as a machine [.1 gun synchronizer, a hollow rotary driving I shaft adapted to be actuated by a. suitable prime mover, a driven shaft keyed-to said driving shaft and adapted to be rotated thereby, a tangential cam arranged on one end of v said driven shaft, and meansfor maintaining I said driven shaftin adjusted positions made possible-by said key connection, a cam fol lower adapted for use as an impulse generator for the firing mechanism of the gun, said i follower being 'sorecessed as to permit rota- I tion of said cam therein and to be thus actuated by said cam for causing reciprocatory movement of said'follower and means for a ,adjusting and maintaining said cam in align- 1 j .ment with said follower;

In testimony whereof, I have signed my name to this specification this 24th day of WINTHROP s. HORTON. 

